Method and System for Interference Suppression Using Information From Non-Listened Base Stations

ABSTRACT

Aspects of a method and system for interference suppression using information from non-listened base stations are provided. A wireless communication device may be operable to receive a raw signal comprising one or more desired signals from one or more serving base transceiver stations (BTSs) and comprising one or more undesired signals from one or more non-listened BTSs. The wireless communication device may be operable to generate first estimate signals that estimate the one or more undesired signals as transmitted by the one or more non-listened BTSs, generate an interference suppressed version of the raw signal based on the first estimate signals, and recover the one or more desired signals from the interference suppressed version of the raw signal. The non-listened BTSs may comprise one or more BTSs that are not serving the wireless communication device and are not involved in a hand off of the wireless communication device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/573,803, filed on Oct. 5, 2009, which makes reference to, claimspriority to and claims benefit of U.S. Provisional Patent ApplicationSer. No. 61/242,524, filed on Sep. 15, 2009. U.S. application Ser. No.12/573,803 and U.S. Provisional Patent Application Ser. No. 61/242,524are hereby incorporated by reference in their entirety.

This application also makes reference to: U.S. patent application Ser.No. 12/582,771, filed on Oct. 21, 2009; U.S. patent application Ser. No.12/604,978, filed on Oct. 23, 2009; U.S. Patent Application Ser. No.61/242,524, filed on Sep. 15, 2009; U.S. patent application Ser. No.12/573,803, filed on Oct. 5, 2009; U.S. patent application Ser. No.12/604,976, filed on Oct. 23, 2009; U.S. Patent Application Ser. No.61/246,797, filed on Sep. 29, 2009; U.S. patent application Ser. No.12/575,879, filed on Oct. 8, 2009; U.S. patent application Ser. No.12/615,237, filed on Nov. 9, 2009; U.S. Patent Application Ser. No.61/288,008, filed on Dec. 18, 2009; U.S. Patent Application Ser. No.61/242,554, filed on Sep. 15, 2009; U.S. patent application Ser. No.12/612,272, filed on Nov. 4, 2009; U.S. patent application Ser. No.12/575,840, filed on Oct. 8, 2009; U.S. patent application Ser. No.12/605,000, filed on Oct. 23, 2009; U.S. patent application Ser. No.12/543,283, filed on Aug. 18, 2009; U.S. patent application Ser. No.12/570,736, filed on Sep. 30, 2009; U.S. patent application Ser. No.12/577,080, filed on Oct. 9, 2009; U.S. patent application Ser. No.12/603,304, filed on Oct. 21, 2009;

Each of the above reference applications is also hereby incorporatedherein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Certain embodiments of the invention relate to networking. Morespecifically, certain embodiments of the invention relate to a methodand system for interference suppression using information fromnon-listened base stations.

2. Background Art

Wideband code division multiple access (WCDMA) is a third generation(3G) cellular technology that enables the concurrent transmission of aplurality of distinct digital signals via a common RF channel. WCDMAsupports a range of communications services that include voice, highspeed data and video communications. One such high speed datacommunications service, which is based on WCDMA technology, is the highspeed downlink packet access (HSDPA) service.

WCDMA is a spread spectrum technology in which each digital signal iscoded or “spread” across the RF channel bandwidth using a spreadingcode. Each of the bits in the coded digital signal is referred to as a“chip”. A given base transceiver station (BTS), which concurrentlytransmits a plurality of distinct digital signals, may encode each of aplurality of distinct digital signals by utilizing a different spreadingcode for each distinct digital signal. At a typical BTS, each of thesespreading codes is referred to as a Walsh code. The Walsh coded digitalsignal may in turn be scrambled by utilizing a pseudo-noise (PN) bitsequence to generate chips. An example of a PN bit sequence is a Goldcode. Each of a plurality of BTS within an RF coverage area may utilizea distinct PN bit sequence. Consequently, Walsh codes may be utilized todistinguish distinct digital signals concurrently transmitted from agiven BTS via a common RF channel while PN bit sequences may be utilizedto distinguish digital signals transmitted by distinct BTSs. Theutilization of Walsh codes and PN sequences may increase RF frequencyspectrum utilization by allowing a larger number of wirelesscommunications to occur concurrently within a given RF frequencyspectrum. Accordingly, a greater number of users may utilize mobilecommunication devices, such as mobile telephones, Smart phones and/orwireless computing devices, to communicate concurrently via wirelesscommunication networks.

A user utilizing a mobile communication device, MU_1, may be engaged ina communication session with a user utilizing a mobile communicationdevice MU_2 via a base transceiver station, BTS_A within wirelesscommunication network. For example, the mobile communication device MU_1may transmit a digital signal to the BTS_A, which the base transceiverstation BTS_A may then transmit to the mobile communication device MU_2.The base transceiver station BTS_A may encode signals received from themobile communication device MU_2 and transmitted to the mobilecommunication device MU_2 by utilizing a Walsh code, W_12, and a PNsequence, PN_A. The mobile communication device MU_2 may receive signalstransmitted concurrently by a plurality of base transceiver stations(BTSs) in addition to the base transceiver station BTS_A within a givenRF coverage area. The mobile communication device MU_2 may process thereceived signals by utilizing a descrambling code that is based on thePN sequence PN_A and a despreading code that is based on the Walsh codeW_12. In doing so, the mobile communication device MU_2 may detect ahighest relative signal energy level for signals received from basetransceiver station BTS_A, which comprise a digital signal correspondingto mobile communication device MU_1.

However, the mobile communication device MU_2 may also detect signalenergy from the digital signals, which correspond to signals from mobilecommunication devices other than the mobile communication device MU_1.The other signal energy levels from each of these other mobilecommunication devices may be approximated by Gaussian white noise, butthe aggregate noise signal energy level among the other mobilecommunication device may increase in proportion to the number of othermobile communication devices whose signals are received at the mobilecommunication device MU_2. This aggregate noise signal energy level maybe referred to as multiple access interference (MAI). The MAI may resultfrom signals transmitted by the base transceiver station BTS_A, whichoriginate from signal received at the base transceiver station BSA_Afrom mobile communication devices other than mobile communication deviceMU_1. The MAI may also result from signals transmitted by the basetransceiver stations BTSs other than the base transceiver station BTS_A.The MAI and other sources of noise signal energy may interfere with theability of MU_2 to successfully decode signals received from MU_1.

An additional source of noise signal energy may result from multipathinterference. The digital signal energy corresponding to the mobilecommunication device MU_2, which is transmitted by the base transceiverstation BTS_A may disperse in a wavefront referred to as a multipath.Each of the components of the multipath may be referred to as amultipath signal. Each of the multipath signals may experience adifferent signal propagation path from the base transceiver stationBTS_A to the mobile communication device MU_2. Accordingly, differentmultipath signals may arrive at different time instants at the mobilecommunication device MU_2. The time duration, which begins at the timeinstant that the first multipath signal arrives at the mobilecommunication device MU_2 and ends at the time instant that the lastmultipath signal arrives at the mobile communication device MU_2 isreferred to as a delay spread. The mobile communication device MU_2 mayutilize a rake receiver that allows the mobile communication device MU_2to receive signal energy from a plurality of multipath signals receivedwithin a receive window time duration. The receive window time durationmay comprise at least a portion of the delay spread time duration.Multipath signals, which are not received within the receive window timeduration may also contribute to noise signal energy.

Further limitations and disadvantages of conventional and traditionalapproaches will become apparent to one of skill in the art, throughcomparison of such systems with some aspects of the present invention asset forth in the remainder of the present application with reference tothe drawings.

BRIEF SUMMARY OF THE INVENTION

A system and/or method is provided for interference suppression usinginformation from non-listened base stations, substantially asillustrated by and/or described in connection with at least one of thefigures, as set forth more completely in the claims.

These and other advantages, aspects and novel features of the presentinvention, as well as details of an illustrated embodiment thereof, willbe more fully understood from the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

FIG. 1 is a diagram illustrating an exemplary wireless communicationsystem, which is operable to provide interference suppression in WCDMA,in accordance with an embodiment.

FIG. 2 is a diagram of an exemplary communication device, which isoperable to provide interference suppression for WCDMA, in accordancewith an embodiment of the invention.

FIG. 3 is a diagram of an exemplary WCDMA receiver with interferencesuppression, in accordance with an embodiment of the invention.

FIG. 4 is a block diagram illustrating an exemplary interferencecancellation module, in accordance with an embodiment of the invention.

FIG. 5 is a flow chart illustrating exemplary steps for suppressinginterference in received signals based on signals received fromnon-listened BTSs, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Certain embodiments of the invention may be found in a method and systemfor interference suppression using information from non-listened basestations. In various embodiments of the invention, one or more circuitsin a wireless communication device may be operable to receive a rawsignal comprising one or more desired signals from one or more servingbase transceiver stations (BTSs) and comprising one or more undesiredsignals from one or more non-listened BTSs. The one or more circuits maybe operable to generate first estimate signals that estimate the one ormore undesired signals as transmitted by the one or more non-listenedBTSs, generate an interference suppressed version of the raw signalbased on the first estimate signals, and recover the one or more desiredsignals from the interference suppressed version of the raw signal. Thenon-listened BTSs may comprise one or more BTSs that are not serving thewireless communication device and are not involved in a handoff of thewireless communication device. The raw signal may be as receivedover-the-air and may comprise, for example, signals for one or moreusers of one or more BTSs, signals from one or more handsets, and/orsignals from non-cellular sources. Furthermore, the various signals thatmake up the raw signal may each be received via one or more paths.Generating the first estimate signals may comprise generating aplurality of potential user signals from the one or more undesiredsignals received from the one or more non-listened BTSs, and scalingeach of the plurality of potential user signals by a corresponding oneof a plurality scaling factors. The plurality of scaling factors may begenerated based on power and noise detected in the plurality ofpotential user signals.

A first portion of the one or more circuits may be dynamically allocatedfor processing the one or more desired signals received from the one ormore serving BTS, and a second portion of the one or more circuits maybe dynamically allocated for processing the one or more undesiredsignals received from the one or more non-listened BTSs. The firstportion of the one or more circuits may be configured based on one ormore scrambling codes associated with the one or more serving BTSs. Thesecond portion of the one or more circuits may be configured based onone or more scrambling codes associated with the one or morenon-listened BTSs. A third portion of the one or more circuits may bedynamically allocated for processing one or more undesired signalsreceived from one or more serving BTSs. The third portion of the one ormore circuits may generate second estimate signals that estimate the oneor more undesired signals as transmitted by the one or more servingBTSs, and the interference suppressed version of the raw signal may begenerated based on the second estimate signals. A third portion of theone or more circuits may be dynamically allocated for processingundesired signals received from one or more handoff BTSs. The thirdportion of the one or more circuits may generate second estimate signalsthat estimate the one or more undesired signals as transmitted by theone or more handoff BTSs, and the interference suppressed version of theraw signal may be generated based on the second estimate signals.

FIG. 1 is an illustration of an exemplary wireless communication system,in accordance with an embodiment. Referring to FIG. 1, there is showncell 100 comprising BTSs 102 and 104, and a BTS 106. Also shown aremobile communication devices MU_1 112 and MU_2 114.

The mobile communication devices MU_1 112 and MU_2 114 may be engaged ina communication via the BTS_A 102. The mobile communication device MU_1112 may transmit signals to the BTS_A 102 via an uplink RF channel 122.In response, the BTS_A 102 may transmit signals to the mobilecommunication device MU_2 114 via a downlink RF channel 124. Signalstransmitted by the BTS_A 102 may comprise chips that are generatedutilizing a scrambling code PN_A. The signals transmitted via RF channel124 may be spread utilizing a spreading code WC_12. The spreading codeWC_12 may comprise an orthogonal variable spreading factor (OVSF) code,for example a Walsh code, which enables the mobile communication deviceMU_2 114 to distinguish signals transmitted by the BTS_A 102 via thedownlink RF channel 124 from signals transmitted concurrently by theBTS_A 102 via other downlink RF channels, for example downlink RFchannel 126. The BTS ion A 102 may utilize one or more OVSF codes,WC_other, when spreading data transmitted via downlink RF channel 126.The one or more OVSF codes, WC_other, may be distinct from the OVSF codeWC 12.

The mobile communication device MU_2 114 may receive MAI signals from RFchannel 126, RF channel 128, and RF channel 130. As stated above,signals received via RF channel 126 may be transmitted by the BTS_A 102.The signals received via RF channel 128 may be transmitted by the BTS B104. The signals transmitted by the BTS n 104 may be scrambled based ona scrambling code PN_B. The signals received via RF channel 130 may betransmitted by the BTS C 106. The signals transmitted by the BTS C 106may be scrambled based on a scrambling code PN_C.

The mobile communication device MU_2 114 may be operable to perform asoft handoff from the current serving BTS_A 102 to any of a plurality ofBTSs located within the cell 100, for example, the BTS B 104.Accordingly, the mobile communication device MU_2 114 may be operable toprocess received signals based on scrambling code PN_A and/or scramblingcode PN_B. In this regard, the mobile communication device MU_2 114 maysend data to the BTS_A 102 and/or the BTS B 104, and data destined formobile communication device MU_2 114 may be received via the BTS_A 102and/or the BTS B 104. Thus, the BTS_A 102 and the BTS B 104 may bereferred to as “listened” BTSs. Conversely, the mobile communicationdevice MU_2 114 may not be operable to perform a soft handoff from thecurrent serving BTS_A 102 to a BTS that is outside of the cell 100—theBTS C 106, for example. In this regard, the mobile communication deviceMU_2 114 may not transmit data to the BTS C 106 or receive data destinedfor the mobile communication device MU_2 114 from the BTS C 106.Accordingly, the BTS C 106 may be referred to as a “non-listened” BTS.

While the desired signal at the mobile communication device MU_2 114 maybe received via RF channel 124, the mobile communication device MU_2 114may also receive signal energy via the RF channels 126 and 128. Thereceived signal energies from the RF channels 126 and/or 128 may resultin MAI, which may interfere with the ability of the mobile communicationdevice MU_2 114 to receive desired signals via RF channel 124.Accordingly, in various aspects of the invention, the mobilecommunication device MU_2 114 is operable to suppress interferenceresulting from undesired signals transmitted by listened BTSs.Additionally, even though the BTS is not a listened BTS, informationtransmitted on the RF channel 130—data transmitted to mobilecommunication devices other than mobile communication device MU_2114—may nevertheless interfere with the desired signals on the RFchannel 124. Accordingly, in various aspects of the invention, themobile communication device MU_2 114 is operable to suppressinterference from the non-listened BTS 106, or non-listened BTSs.

Although FIG. 1 depicts communication between two mobile devices via asingle BTS, the invention is not so limited. For example, aspects of theinvention may be equally applicable regardless of the origin of datacommunicated wirelessly to the mobile communication device 114.

FIG. 2 is a diagram of an exemplary communication device, which mayutilize interference suppression for WCDMA, in accordance with anembodiment of the invention. Referring to FIG. 2, there is shown atransceiver system 200, a receiving antenna 222, and a transmittingantenna 232. The transceiver system 200 may comprise a receiver 202, atransmitter 204, a processor 206, an interference cancellation module210 and a memory 208. The interference cancellation module 210 maycomprise a plurality of per cell modules 212 a, 212 b, 212 c and 212 d.Although a separate receiver 202 and transmitter 204 are illustrated byFIG. 2, the invention is not limited. In this regard, the transmitfunction and receive function may be integrated into a singletransceiver block. The transceiver system 200 may also comprise aplurality of transmitting antennas and/or a plurality of receivingantennas, for example to support diversity transmission and/or diversityreception. Various embodiments of the invention may comprise a singleantenna, which is coupled to the transmitter 204 and receiver 202 via atransmit and receive (T/R) switch. The T/R switch may selectively couplethe single antenna to the receiver 202 or to the transmitter 204 underthe control of the processor 206, for example.

The receiver 202 may comprise suitable logic, circuitry, interfacesand/or code that may be operable to perform receive functions that maycomprise PHY layer function for the reception or signals. These PHYlayer functions may comprise, but are not limited to, the amplificationof received RF signals, generation of frequency carrier signalscorresponding to selected RF channels, for example uplink or downlinkchannels, the down-conversion of the amplified RF signals by thegenerated frequency carrier signals, demodulation of data contained indata symbols based on application of a selected demodulation type, anddetection of data contained in the demodulated signals. The RF signalsmay be received via the receiving antenna 222. The receiver 202 mayprocess the received RF signals to generate baseband signals. Achip-level baseband signal may comprise a plurality of chips. Thechip-level baseband signal may be descrambled based on a PN sequence anddespread based on an OVSF code, for example a Walsh code, to generate asymbol-level baseband signal. The symbol-level baseband signal maycomprise a plurality of data symbols. The receiver 202 may comprise arake receiver, which in turn comprises a plurality of rake fingers toprocess a corresponding plurality of received multipath signals.

The transmitter 204 may comprise suitable logic, circuitry, interfacesand/or code that may be operable to perform transmit functions that maycomprise PHY layer function for the transmission or signals. These PHYlayer functions may comprise, but are not limited to, modulation ofreceived data to generate data symbols based on application of aselected modulation type, generation of frequency carrier signalscorresponding to selected RF channels, for example uplink or downlinkchannels, the up-conversion of the data symbols by the generatedfrequency carrier signals, and the generation and amplification of RFsignals. The RF signals may be transmitted via the transmitting antenna232.

The memory 208 may comprise suitable logic, circuitry, interfaces and/orcode that may enable storage and/or retrieval of data and/or code. Thememory 208 may utilize any of a plurality of storage mediumtechnologies, such as volatile memory, for example random access memory(RAM), and/or non-volatile memory, for example electrically erasableprogrammable read only memory (EEPROM).

The interference cancellation module 210 may comprise suitable logic,circuitry and/or code that are operable to suppress interferencesignals, relative to a desired signal, in a received signal. Thereceived signal may comprise one or more desired signals and one or moreinterference signals. The interference cancellation module 210 maygenerate an interference suppressed versions of the one or more signalsin which the signal level for the interference signals is reducedrelative to the signal level for the desired signal. In this regard, theinterference suppressed version of the signal may be an estimate of thesignal as transmitted.

Each of the per-cell modules 212 a, 212 b, 212 c, and 212 d may comprisesuitable logic, circuitry, interfaces, and/or code that may be operableto generate an interference suppressed version of a signal received froma particular listened or non-listened BTS. Each of the per-cell modules212 a, 212 b, 212 c and 212 d may be associated with a particular signalsource, where the signal source may be identified by a particular PNsequence and may correspond to a particular transmit antenna of aparticular BTS. In this regard, each of the per-cell modules 212 a, 212b, 212 c, and 212 d may be individually configured with a PN sequencecorresponding to the associated BTS. In generating a an interferencesuppressed version of a received signal, each of the per-cell modules212 a, 212 b, 212 c and 212 d may be operable to perform a weightingiteration, one or more weighting and addback iterations, and/or anaddback iteration on the received signal.

In operation, the receiver 202 may receive signals via the receivingantenna 222. In various embodiments of the invention, the receiver 202may utilize a plurality of receiving antennas. In an exemplaryembodiment of the invention, the receiver 202 may comprise a rakereceiver. The receiver 202 may communicate signals to the processor 206and/or to the interference cancellation module 210.

The receiver 202 may generate timing information that corresponds toeach of the fingers in the rake receiver portion of the receiver 202.Each of the fingers in the rake receiver may process a distinct one of aplurality of multipath signals that are received within a delay spreadtime duration. In instances where the receiver 202 utilizes a pluralityof receiving antennas, the receiver 202 may associate each of theplurality of multipath signals with a receiving antenna through whichthe multipath signals was received by the receiver 202. Based onreceived multipath signals, the receiver 202 may generate chip-levelbaseband signals.

The receiver 202 may communicate the chip-level baseband signals and/orgenerated timing information to the interference cancellation module210. The rake receiver 202 may generate one or more descrambled basebandsignals for each receive antenna utilized by the receiver 202 based on acorresponding selected one or more PN sequences. The descrambledbaseband signals and/or generated timing information may be communicatedto the processor 206. For example, referring to FIG. 1, the rakereceiver 202 associated with mobile communication device MU_2 may selecta PN sequence, PN_A, which may then be utilized to generate thedescrambled baseband signals from the chip-level baseband signal. Thedescrambled baseband signals communicated to the processor 206 maycomprise common pilot channel (CPICH) information.

In instances where the receiver 202 utilizes a plurality of receivingantennas, the receiver 202 may generate one or more descrambled basebandsignals for each receiving antenna based on the corresponding multipathsignals received by the receiver 202. Each of the descrambled basebandsignals, generated from signals received via a corresponding receivingantenna, may be respectively communicated to the processor 206.

The processor 206 may utilize CPICH information to compute a pluralityof channel estimate values or, in various embodiments of the invention,the receiver 202 may compute the channel estimate values. The processor206 and/or receiver 202 may compute one or more channel estimate valuescorresponding to each multipath signal, which was transmitted by a giventransmit antenna of a given BTS and received at a finger in the rakereceiver via a given receiving antenna. The computed channel estimatevalues may be represented as a channel estimate matrix, H_(bts,rx,fgr,)where bts represents a numerical index that is associated with a givenBTS, rx represents a numerical index that is associated with a givenreceiving antenna, and fgr is a numerical index that is associated witha given rake finger. The processor 206 may be operable to communicatethe computed channel estimate values to the receiver 202 and/or to theinterference cancellation module 210 and/or to the memory 208. Theprocessor 206 may compute and/or select one or more interferencecancellation parameter values, which control the signal interferencecancellation performance of the interference cancellation module 210.The processor 206 may communicate the interference cancellationparameter values to the interference cancellation module 210 and/or tothe memory 208.

The processor 206 may identify one or more BTSs with which thetransceiver 200 may communicate. The one or more BTSs may comprise acurrent serving BTS and one or more handoff BTSs. The processor 206 maydetermine a PN sequence for each of the identified one or more BTSs. Theprocessor 206 may configure one or more of the per-cell modules 212 a,212 b, 212 c and 212 d with a corresponding selected one or more PNsequences, wherein each selected PN sequence may be selected from theset of determined PN sequences.

In various embodiments of the invention, the processor 206 may identifyone or more BTSs, which with respect to the transceiver 200, are neithera current serving BTS nor a handoff BTS. These base stations may bereferred to as non-listened BTSs. The processor 206 may determine a PNsequence for each identified non-listened BTS. The processor 206 mayconfigure one or more of the per-cell modules 212 a, 212 b, 212 c and212 d with a corresponding selected PN sequence for one or morenon-listened BTSs.

The processor 206 may also determine the number of receiving antennas,which are utilized by the transceiver 200 to receive signals. For eachreceiving antenna, the processor 206 may configure a correspondingplurality of per-cell modules 212 a, 212 b, 212 c and 212 d with a PNsequence selected from the set of determined PN sequences.

The following is a discussion of exemplary operation for the per-cellmodule 212 a. The operation of per-cell modules 212 b, 212 c and 212 dis substantially similar to the operation of per-cell module 212 a asdescribed below.

The processor 206 may also configure the per-cell module 212 a withinterference cancellation parameter values. In various embodiments ofthe inventions, the interference cancellation parameter valuesconfigured for per-cell module 212 a may be equal to correspondinginterference cancellation parameter values utilized by other per-cellmodules 212 b, 212 c and 212 d. In other embodiments of the invention,the interference cancellation parameter values configured for theper-cell module 212 a may be selected independently from thecorresponding interference cancellation parameter values utilized byother per-cell modules 212 b, 212 c and 212 d.

The processor 206 may associate one or more rake fingers with theper-cell module 212 a. The processor 206 may communicate the channelestimate values, H_(bts,rx,fgr,) corresponding to each finger, fgr,associated with the per-cell module 212 a. The receiver 202 maycommunicate timing information for each corresponding rake finger. Theprocessor 206 may configure the per-cell module 212 a with a PN sequencecorresponding to a BTS.

In an exemplary embodiment of the invention, the processor 206 mayconfigure the per-cell module 212 a with the IN sequence for a servingBTS 102, for example PN_A. Accordingly, the receiver 202 may communicatechannel estimate values, H_(bts,rx,fgr,) and timing information forsignals transmitted via RE channel 124 and received via receivingantenna 222 for each corresponding finger in the rake receiver that isassociated with the per-cell module 212 a. The per-cell module 212 a maygenerate and/or retrieve a plurality of OVSF codes and/or one or moreinterference cancellation parameter values in the memory 208. In variousembodiments of the invention, the plurality of OVSF codes may compriseone or more OVSF codes, which may potentially be utilized by the BTS 102to generate signals transmitted via RF channel 124. In an exemplaryembodiment of the invention, the plurality of OVSF codes comprises 256distinct Walsh Codes. While the per-cell module 212 a is associated withthe serving BTS 102, each of the remaining per-cell modules 212 b, 212c, and 212 d may be associated with a different listening ornon-listening BTS.

In another exemplary embodiment of the invention, the processor 206 mayconfigure the per-cell module 212 a with the PN sequence for a handoffBTS 104, for example PN_B. the receiver 202 may communicate channelestimate values, H_(bts,rx,fgr,) and timing information for signalstransmitted via RF channel 128 and received via receiving antenna 222for each corresponding finger in the rake receiver that is associatedwith the per-cell module 212 a. While the per-cell module 212 a isassociated with the handoff BTS 104, each of the remaining per-cellmodules 212 b, 212 c, and 212 d may be associated with a differentlistening or non-listening BTS.

In another exemplary embodiment of the invention, the processor 206 mayconfigure the per-cell module 212 a with the PN sequence for anon-listened BTS 106, for example PN_C. Accordingly, the receiver 202may communicate channel estimate values, H_(bts,rx,fgr,) and timinginformation for signals transmitted via RF channel 130 and received viareceiving antenna 222 for each corresponding finger in the rake receiverthat is associated with the per-cell module 212 a. While the per-cellmodule 212 a is associated with the non-listened BTS 104, each of theremaining per-cell modules 212 b, 212 c, and 212 d may be associatedwith a different listening or non-listening BTS.

In instances in which the transceiver system 200 utilizes a plurality ofreceiving antennas, for example the receiving antennas 222_1 and 22.2_2,the transceiver system 200 may utilize receive diversity. In a receivediversity system, the receiver 202 may receive a first set of signalsvia the receiving antenna 222_1 and a second set of signals via thereceiving antenna 222_2. The processor 206 may configure the per-cellmodule 212 a, as described above, to receive signals via the receivingantenna 222_1, while the processor 206 configures the per-cell module212 b, as described above, to receive signals via the receiving antenna222_2.

In a transceiver system 200, which utilizes receive diversity, theprocessor 206 may compute a first set of channel estimate valuescorresponding to receiving antenna 222_1 and a second set of channelestimate values corresponding to receiving antenna 222_2. The computedchannel estimate values may be represented as a channel estimate matrix,H_(bts,rx,fgr,) where rx represents a numerical index that is associatedwith a given receiving antenna. The receiver 202 may generate a firstset of timing information for signals received via the receiving antenna222_1 and the receiver 202 may generate a second set of timinginformation for signals received via the receiving antenna 222_2. Invarious embodiments of the invention, which utilize receive diversity,the receiver 202 and/or the interference cancellation module 210 mayalso process signals that are transmitted by BTSs, which utilize signaltransmission diversity.

After being configured for interference cancellation operation, theper-cell module 212 a may receive one or more multipath signals from thereceiver 202 via a corresponding one or more rake fingers that areassociated with the per-cell module 212 a. The signals received by theper-cell module 212 a may comprise chip-level baseband signals. Theper-cell module 212 a may combine the received one or more chip-levelsignals by utilizing the corresponding channel estimate values, and/orthe corresponding timing information, based on, for example, maximalratio combining (MRC) and/or equal gain combining (EGC). The per-cellmodule 212 a may utilize the configured PN sequence to descramble thecombined chip-level signal. Based on this descrambling of the combinedsignals, the per-cell module 212 a may generate descrambled signals.

The per-cell module 212 a may process the descrambled signals byutilizing each of the plurality of OVSF codes to generate acorresponding plurality of symbol-level signals. Each symbol-levelsignal associated with an OVSF code may be referred to herein as acorresponding user signal, although it should be noted that multipleOVSF codes may be associated with a single user and thus there is notnecessarily a one-to-one correspondence between OVSF codes and users.For example, a signal associated with a j^(th) OVSF code may be referredto as a j^(th) user signal. Referring to FIG. 1, for example, the OVSFcode WC_12 may be associated with a user signal that is transmitted frombase station A 102 to the mobile telephone MC_2 114.

The per-cell module 212 a may compute a signal power level value and anoise power level value corresponding to each of the user signals. Basedon the computed signal power level value, noise power level value andthe one or more interference cancellation parameter values, the per-cellmodule 212 a may compute a weighting factor value corresponding to eachuser signal. The plurality of weighting factor values associated witheach BTS may be represented as a weighting factor matrix, A_(bts,) wherebts represents a numerical index value that is associated with a givenBTS. In an exemplary embodiment of the invention, the weighting factorvalues for a given BTS may be computed as illustrated by the followingequations:

$\begin{matrix}{z_{j} \cong \frac{\lambda \; x_{j}^{2}}{{\lambda \; x_{j}^{2}} + y_{j}^{2}}} & \left\lbrack {1a} \right\rbrack\end{matrix}$

when

x_(j) ²>γy_(j) ²   [1b]

and

z_(j)=0   [1c]

when

x_(j) ²<γy_(j) ²   [2d]

where z_(j) represents the weighting factor value for the j^(th) usersignal and j may be, for example, an integer from 0 to J; x_(j) ²represents the signal power level value for the j^(th) user signal,which was generated by descrambling a received signal based on a PNsequence for the given BTS and despreading the descrambled signalutilizing the OVSF code associated with the j^(th) user; y_(j) ²represents the noise power level value for the j^(th) user signal, whichwas generated by descrambling the received signal based on the PNsequence for the given BTS and despreading the descrambled signalutilizing the OVSF code associated with the j^(th) user; and λ and γrepresent interference cancellation parameter values.

The weighting factor values z_(j) may correspond to a signal to noiseratio (SNR) measure for the j^(th) user signal. Values for z_(j) may bewithin the range 0≦z_(j) ²≦1. In one regard, values of z_(j) may be an apriori measure of confidence that a given user signal comprises validsignal energy that was transmitted by the BTS.

In various embodiments of the invention, the per-cell module 212 a maybe operable to process received chip-level signals by performing aweighting iteration, one or more weighting and addback iterations and anaddback iteration. During the weighting iteration, the per-cell module212 a may receive a chip-level multipath signal from each associatedfinger and generate a corresponding estimated chip-level signal for eachassociated finger. During the one or more weighting and addbackiterations, the per-cell module 212 a may receive a residual chip-levelsignal from each associated finger and generate a correspondingincremental chip-level signal for each associated finger. During theaddback iteration, the per-cell module 212 a may receive an updatedresidual chip-level signal from each associated finger and generate acorresponding interference suppressed chip-level signal for eachassociated finger. The interference suppressed chip-level signal maycorrespond to an interference suppressed version of the receivedmultipath signal. The interference suppressed chip-level signals may beoutput to each corresponding rake finger. Each of the rake fingers maythen process its respective interference suppressed chip-level signals.

FIG. 3 is a diagram of an exemplary WCDMA receiver with interferencesuppression, in accordance with an embodiment of the invention.Referring to FIG. 3, there is shown a WCDMA receiver 300 comprising aninterference cancellation module 302, a delay buffer 304, a HSDPAprocessor 306, an HSDPA switching device 308, interference cancellation(IC) bypass switching device 310, and a plurality of rake fingers 312,314 and 316. The interference cancellation module 302 may correspond tothe interference cancellation module 210 as presented in FIG. 2. Therake fingers 312, 314 and 316 represent fingers in a rake receiver. Inan exemplary embodiment of the invention, the HSDPA switching device 308and the IC bypass switching device 310 may be configured by theprocessor 206.

The delay buffer 304 may comprise suitable logic, circuitry, interfacesand/or code that may be operable to receive a burst of a chip-levelsignal 324 as input at a given input time instant and output it as aburst of a chip-level signal 326 at a subsequent output time instant.The time duration between the input time instant and the output timeinstant may be referred to as a delay time duration. In an exemplaryembodiment of the invention, the delay time duration corresponds to 512chips.

The HSDPA processor 306 may comprise suitable logic, circuitry,interfaces and/or code that may be operable to provide HSDPA processingof received signals.

In operation, the HSDPA switching device 308 may comprise suitablelogic, circuitry, interfaces and/or code that are operable to select aninput signal to the HSDPA processor 306. As illustrated with respect toFIG. 3, the HSDPA switching device 308 is configured so that it isoperable to supply an interference suppressed signal 328, generated bythe interference cancellation module 302, as an input to the HSDPAprocessor 306. As indicated in FIG. 3, this configuration of the HSDPAswitching device 308 may result in the HSDPA switching device 308operating in a HSDPA interference cancellation (IC) mode.

The HSDPA switching device 308 may also be configured so that it isoperable to supply the baseband signal 324, generated by the receiver202, as an input to the HSDPA processor 306. As indicated in FIG. 3,this configuration of the HSDPA switching device 308 may result in theHSDPA switching device 308 operating in a normal HSDPA mode.

The HSDPA switching device 308 may also be configured such that no inputsignal is supplied to the HSDPA processor 306. As indicated in FIG. 3,this configuration of the HSDPA switching device 308 may result in theHSDPA switching device 308 operating in a HSDPA data path off mode.

The IC bypass switching device 310 may comprise suitable logic,circuitry, interfaces and/or code that are operable to select an inputsignal to the rake fingers 312, 314 and 316. As illustrated with respectto FIG. 3, the IC bypass switching device 310 is configured so that itis operable to supply an interference suppressed signal 322, generatedby the interference cancellation module 302, as an input to the rakefingers 312, 314 and 316.

The IC bypass switching device 310 may also be configured so that it isoperable to supply a signal 326, which is output from the delay buffer304, as an input to the rake fingers 312, 314 and 316. The signal 326output from the delay buffer 304 may comprise a time-delayed, andpossibly up-sampled or down-sampled, version of the signal 324 generatedby the receiver 202. As indicated in FIG. 3, the signal 326 output fromthe delay buffer 304 may comprise unsuppressed interference.

Each of the rake fingers 312, 314 and 316 may receive, as input, thechip-level baseband signal 324 generated by the receiver 202. Based onthe input baseband signal 324 from the receiver 202, each rake finger312, 314 and 316 may generate channel estimates and rake finger timinginformation. In various embodiments of the invention, each rake finger312, 314 and 316 may generate the channel estimates and/or rake fingertiming information for selected multipath signals based on CPICH datareceived via the input baseband signal 324 received from the receiver202. In an exemplary embodiment of the invention, which comprises areceive diversity system, channel estimates and/or rake finger timinginformation may be generated for RF signals received at the receiver 202via at least a portion of a plurality of receiving antennas. Each rakefinger 312, 314 and 316 may communicate, as one or more signals 318, itsrespective channel estimates, rake finger timing information, scalingfactors K_(fgr,) scrambling codes associated with one or more BTSs,and/or other information to the interference cancellation module 302.

In various embodiments of the invention, the interference cancellationmodule 302 may receive chip-level signals 326 from the delay buffer 304.Based on the channel estimates, rake finger timing, and/or otherinformation communicated via the signal(s) 318, the interferencecancellation module 302 may select individual multipath signals from thechip-level signals 326 received via the delay buffer 304. Based on theinterference cancellation parameters 320, which may be as described withrespect to FIG. 2, the interference cancellation module 302 may processthe received chip-level multipath signal 326 utilizing an iterativemethod for interference cancellation, in accordance with an embodimentof the invention.

The chip-level signals 326 received from the delay buffer 304 maycomprise a plurality of multipath signals received via one or morereceive antennas from one or more transmit antennas of one or more BTSs.The interference cancellation module 302 may be configurable to assignsignal processing resources to perform the iterative method ofinterference cancellation for selected multipath signals. The processor206 may configure the interference cancellation module 302 to receivemultipath signals from one or more transmit antennas of one or morelistened and/or non-listened BTSs. In an exemplary embodiment of theinvention, which comprises a receive diversity system, the selectedmultipath signals may be received via one or more of a plurality ofreceiving antennas. The processor 206 may configure the interferencecancellation module 302 for receive diversity.

The interference cancellation module 302 may receive interferencecancellation parameters 320 from the processor 206 and/or from thememory 208. In an exemplary embodiment of the invention, theinterference cancellation module 302 may generate and/or retrieve PNsequences and/or OVSF codes from the memory 208. The PN sequences may begenerated on the fly based on the code structure utilized by the BTSand/or based on timing information associated with the BTS. Theinterference cancellation module 302 may retrieve and/or generate a PNsequence for each of the one or more transmit antennas of the one ormore BTSs from which the interference cancellation module 302 isconfigured to attempt to receive a signal and/or for one or more BTSsthat are not listened to, but still may interfere with desired signals.

In various embodiments of the invention in which the receiver 202utilizes a plurality of receiving antennas and/or receives data from aplurality of transmit antennas, data received via the symbol-levelsignals corresponding to the plurality of receiving antennas and/ortransmit antennas may be decoded by utilizing various diversity decodingmethods. Various embodiments of the invention may also be practiced whenthe receiver 202 is utilized in a multiple input multiple output (MIMO)communication system. In instances where the receiver 202 is utilized ina MIMO communication system, data received via the symbol-level signals,received via the plurality of receiving antennas, may be decoded byutilizing various MIMO decoding and/or diversity decoding methods.

FIG. 4 is a block diagram illustrating an exemplary interferencecancellation module, in accordance with an embodiment of the invention.Referring to FIG. 4, there is shown an interference cancellation module302 comprising a channel estimate (CHEST) pre-processing block 401,interference cancellation per-cell modules 403A, 403B, 403C, 403D, aninterference cancellation subtractor 405, an HSDPA interpolation anddelay block 407, a finger MUX 409, and an interpolator 411.

The CHEST pre-processing block 401 may comprise suitable circuitry,logic, interfaces, and/or code that may be operable to normalize channelestimate information input as signal 412 to the per-cell Modules 403 andthe interpolator 411. The normalization may be based on channel estimateand rake finger timing and scaling information 318 received from therake fingers 312, 314, and 316.

The subtractor 405 may comprise suitable circuitry, logic, interfaces,and/or code that may be operable to subtract estimated signals fromreceived signals as part of the generation of an interference suppressedversion of the received signals. The subtractor 405 may be operable toreceive, as inputs, signals generated by the Per-Cell modules 403A-403Dthat may be interpolated by the interpolator 411, as well as bursts ofthe delayed received signal 326 from the delay buffer 304.

The HSDPA interpolation and delay module 407 may comprise suitablecircuitry, logic, interfaces, and/or code that may be operable toprovide a bypass path for signals received from the delay buffer 304.The HSDPA interpolation and delay module 407 may, for example,interpolate cx2 samples to cx16 samples, and may introduce a delay thatequals the delay of the interference cancellation module 302 whenoperating in interference cancellation mode.

The finger MUX 409 may comprise suitable circuitry, logic, interfaces,and/or code that may be operable to select from the plurality of signals420 generated by the Per-Cell modules 403A-403D, the input signal fromthe delay buffer 304, or a non-cancelling finger input 424. In thismanner, the finger MUX 409 may enable a pass-through mode, aninterference cancelling mode, or a non-cancelling mode. In variousembodiments of the invention, the finger MUX 409 may be operable toprocess the interference suppressed signals 420 generated by theper-cell modules 403A-403D in order to maintain compatibility withlegacy rake receivers. In this regard, the signals 420 may be processedbased on finger timing information and/or parameters to reintroducechannel effects, such as multipath effects, expected by the rakefingers. In this manner, the interference suppression module 302 may beadded to existing rake receiver designs with minimal redesign ofexisting receiver components.

The interpolator 411 may comprise suitable circuitry, logic, interfaces,and/or code that may be operable to interpolate a received signal, suchas a cx1 signal and output a cx2 signal, for example.

The Per-Cell modules 403A-403D may each comprise suitable circuitry,logic, interfaces, and/or code that may be operable to generate anestimate of a multi-user (e.g., WCDMA) and/or multipath chip-levelsignal transmitted by an associated BTS. The per-cell modules 403A-403Dmay process bursts—256-chip bursts, for example—of a multipath,multi-user signal. In this regard, a received signal 326 processed bythe modules 403A-403D may comprise information received via one or moreRF paths via one or more receive antennas from one or more transmitantennas of one or more BTSs, each BTS having up to J users. In thisregard, each of the modules 403A-403D may be allocated for processingsignals from a particular transmit antenna of a particular BTS and asignal from a particular transmit antenna may be received over one ormore paths via one or more receive antennas. Accordingly, each of themodules 403A-403D may be operable to compensate for multipath effects,suppress interference from BTSs other than an associated or “serving”BTS, and suppress interference between users of the associated or“serving” BTS.

In an exemplary embodiment of the invention, the four Per-Cell modules403A-403D may be operable to cancel and/or suppress interference fromfour non-diversity transmit (Tx) cells, two Tx diversity cells, one Txdiversity cell and two non-Tx diversity cells, one Tx diversity cellwith two scrambling codes per antenna, and/or one non Tx-diversity cellthat has four scrambling codes. However, the invention need not be solimited, and may support any number of cells depending on the number ofPer-Cell modules integrated in the interference cancellation module.

In operation the delayed received signal 326 may be conveyed to thesubtractor 405 in bursts, and the bursts may be stored in the residuebuffer 413 which may be operable to store, for example, 3×256 chipsworth of samples. The residue buffer 413 may also generate polyphasesamples for each of the per-cell modules 403A-403D. In an exemplaryembodiment of the invention, the signal 326 may be conveyed in 256-chipbursts, with a time between bursts equal to a 256-chip time period. Thesignal 318 is another input to the interference cancellation module 302and may comprise the channel estimation, time tracking, and/orscrambling code information from the Rake fingers.

In HSDPA pass-through mode, the signal 326 may be routed via the HSDPAinterpolation and delay module 407, which may, for example, interpolateCx2 samples to Cx16 samples and introduce a fixed delay that equals theinterference cancellation module 320 delay as if operating in HSDPAcanceling mode. For pass-through mode, the signal 326 may go directly tothe finger MUX 409, where it may be interpolated and delayed beforebeing sent to one or more associated rake fingers such as 312, 314, and316. The delay may equal the interference cancellation module 320 delayas if the block were operating in canceling mode.

In instances where the interference cancellation module 320 is engaged,where at least one rake finger is in the “canceling mode,” or HSDPA isin the canceling mode, the signal 236 may go into the subtractor 405.The interpolator 411 may interpolate the estimated signals 416 a-416 doutput by the per-cell modules 403 and sequentially output theinterpolated versions of the estimated signals 416 a-416 d to thesubtractor 405 as signal 418. The subtractor 405 may subtract theinterpolated estimated signals 418 from the input signal 326 stored inthe buffer 413. The residual signal stored in the residue buffer 413 maybe utilized for further signal estimation in the per-cell modules403A-403D. In this regard, iterative processing may be utilized forinterference suppression. The subtractor 405 may also generate the“canceling mode” HSDPA output data stream 422 and the “non-cancelingmode” rake finger output data stream 424.

Each of the per-cell modules 403A-403D may be operable to estimate areceived signal for each of the J OVSF codes associated with aparticular BTS and/or a particular BTS scrambling code. The estimatedsymbol-level signals for the J codes may be summed up and reconstructedwith the channel estimation to convert them back to chip-level signals416. The chip-level estimated signals 416 may be fed back into thesubtractor 405. Each of the per-cell modules 403A-403D may receivescrambling code information, associated finger channel estimation andtime tracking information from the CHEST pre-processing module 401 andthe output 414 from the subtractor 405. Each of the per-cell modules403A-403D may be associated with one transmit antenna from a cell. Inthe case of no Tx diversity, each cell may be associated with oneper-cell module; in the case of Tx diversity, the PRISM per-cell moduleis associated with one transmit antenna out of the two transit antennaof a cell.

FIG. 5 is a flow chart illustrating exemplary steps for suppressinginterference in received signals based on signals received fromnon-listened BTSs, in accordance with an embodiment of the invention.Referring to FIG. 5, the exemplary steps may begin with step 502 inwhich a wireless communication device, such as the mobile communicationdevices MU_1 112 and MU_2 114 of FIG. 1, is powered up and beginsreceiving a raw signal, wherein the raw signal comprises desired andundesired signals. In this regard, the raw signal may comprise signalsfor one or more users of one or more BTSs, signals from one or morehandsets, and/or signals from non-cellular sources. Furthermore, thevarious signals in the raw signal may each be received via one or morepaths. In step 504, logic, circuitry, interfaces, and/or code, such asthe per-cell modules 403 a-403 d, may be allocated for processing thedesired and/or undesired signals, each desired and/or undesired signalhaving been transmitted by a BTS utilizing an associated scramblingcode—a PN sequence, for example. That is, in various embodiments of theinvention, each of the per-cell modules 403 may be allocated forprocessing signals associated with a particular BTS scrambling code. Inthis regard, each of the per-cell modules 403 may be allocated to aserving BTS, a handoff BTS, or a non-listening BTS. Allocation andreallocation of the per-cell modules 403 may be dynamic during operationof the wireless communication device. For example, one or more of theper-cell modules 403 may be allocated and/or reallocated as the mobilecommunication device travels and one or more BTSs come into range and/orone or more BTSs go out of range.

In step 506, received signals may be iteratively processed to generatean interference suppressed version of the received raw signal. In thisregard, each of the per-cell modules 403 may generate one or moreestimates of a signal transmitted on its associated scrambling code. Instep 508, the interference suppressed signal may be output to the fingerMUX which may re-introduce finger timing delays and/or perform otherprocessing to re-introduce channel effects that the rake expects to bepresent in the signal. In this regard, the re-introduction is performedto be compatible with a legacy rake receiver, and is not necessary inall embodiments of the invention. In step 510, the signal may be furtherprocessed to recover the desired signal.

Various aspects of a method and system for interference suppressionusing information from non-listened base stations are provided. In anexemplary embodiment of the invention, one or more circuits in awireless communication 114 (FIG. 1), may be operable to receive a rawsignal 324 (FIG. 3) comprising one or more desired signals from one ormore serving BTSs, such as the BTS 102 (FIG. 1), and comprising one ormore undesired signals from one or more non-listened BTSs, such as theBTS 106 (FIG. 1). The one or more circuits may be operable to generate afirst estimate signal 420 that estimates the one or more undesiredsignals as transmitted by the one or more non-listened BTSs, generate aninterference suppressed version of the raw signal 324 based on the firstestimate signal 420, and recover the one or more desired signals fromthe interference suppressed version of the raw signal. The one or morenon-listened BTSs may comprise BTSs that are not serving the wirelesscommunication device 114 and are not involved in a handoff of thewireless communication device 114. The raw signal 324 may be as receivedover-the-air and may comprise, for example, signals for one or moreusers of one or more BTSs, signals from one or more handsets, and/orsignals from non-cellular sources. Furthermore, the various signals thatmake up the raw signal may each be received via one or more paths.Generating the first estimate signal 420 may comprise generating aplurality of potential user signals from the one or more undesiredsignals received from the one or more non-listened BTSs 106, and scalingeach of the plurality of potential user signals by a corresponding oneof a plurality of scaling factors, z. The scaling factors, z, may begenerated based on power and noise detected in the plurality ofpotential user signals.

A first portion of the one or more circuits in the wirelesscommunication device 114 may be dynamically allocated for processing theone or more desired signals received from the one or more serving BTSs,such as the BTS 102, and a second portion of the one or more circuits inthe wireless communication device 114 may be dynamically allocated forprocessing the one or more undesired signals received from the one ormore non-listened BTSs, such as the BTS 106. The first portion of theone or more circuits may be configured based on one or more scramblingcodes associated with the one or more serving BTSs. The second portionof the one or more circuits may be configured based on one or morescrambling codes associated with the one or more non-listened BTSs. Athird portion of the one or more circuits may be dynamically allocatedfor processing one or more undesired signals received from one or moreserving BTSs. The third portion of the one or more circuits may generatesecond estimate signals 420 that estimate the one or more undesiredsignals transmitted by the one or more serving BTSs, and theinterference suppressed version of the raw signal may be generated basedon the second estimate signals. A third portion of the one or morecircuits in the wireless communication device 104 may be dynamicallyallocated for processing undesired signals received from one or morehandoff BTSs, such as the BTS 104 (FIG. 1). The third portion of the oneor more circuits may generate second estimate signals that estimate oneor more undesired signals received from one or more handoff BTSs, andthe interference suppressed version of the raw signal may be generatedbased on the second estimate signals.

Another embodiment of the invention may provide a machine and/orcomputer readable storage and/or medium, having stored thereon, amachine code and/or a computer program having at least one code sectionexecutable by a machine and/or a computer, thereby causing the machineand/or computer to perform the steps as described herein forinterference suppression using information from non-listened basestations.

Accordingly, the present invention may be realized in hardware,software, or a combination of hardware and software. The presentinvention may be realized in a centralized fashion in at least onecomputer system, or in a distributed fashion where different elementsare spread across several interconnected computer systems. Any kind ofcomputer system or other apparatus adapted for carrying out the methodsdescribed herein is suited. A typical combination of hardware andsoftware may be a general-purpose computer system with a computerprogram that, when being loaded and executed, controls the computersystem such that it carries out the methods described herein.

The present invention may also be embedded in a computer programproduct, which comprises all the features enabling the implementation ofthe methods described herein, and which when loaded in a computer systemis able to carry out these methods. Computer program in the presentcontext means any expression, in any language, code or notation, of aset of instructions intended to cause a system having an informationprocessing capability to perform a particular function either directlyor after either or both of the following: a) conversion to anotherlanguage, code or notation; b) reproduction in a different materialform.

While the present invention has been described with reference to certainembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted withoutdeparting from the scope of the present invention. In addition, manymodifications may be made to adapt a particular situation or material tothe teachings of the present invention without departing from its scope.Therefore, it is intended that the present invention not be limited tothe particular embodiment disclosed, but that the present invention willinclude all embodiments falling within the scope of the appended claims.

1. A wireless communication device, comprising: an interferencecancellation module configured to process a multipath component signalfrom a received signal to provide an interference suppressed signal; anda processor configured to generate an interference cancellationparameter corresponding to the multipath component, wherein theinterference cancellation module is further configured to utilize theinterference cancellation parameter to provide the interferencesuppressed signal.
 2. The wireless communication device of claim 1,wherein the received signal comprises: a plurality of listened ornon-listened base-transceiver station (BTS) component signals.
 3. Thewireless communication device of claim 1, wherein the interferencecancellation module is further configured to utilize a weighting factorvalue, the weighting factor value being based on the interferencecancellation parameter and a signal metric of the multipath componentsignal, to provide the interference suppressed signal.
 4. The wirelesscommunication device of claim 3, wherein the signal metric comprises: asignal power level or a noise power level of the multipath componentsignal.
 5. The wireless communication device of claim 1, wherein themultipath component signal is from among a plurality of multipathcomponent signals, and wherein the interference cancellation module isfurther configured to separately process the plurality of multipathcomponent signals.
 6. The wireless communication device of claim 5,wherein the interference cancellation module is further configured toallocate the plurality of multipath component signals for separateprocessing according to a pseudo-noise (PN) sequence or an orthogonalvariable spreading factor (OVSF) code.
 7. The wireless communicationdevice of claim 5, wherein a separately processed multipath componentsignal is from among a plurality of source-specific user signals,wherein the interference cancellation parameter is from among aplurality of interference cancellation parameters, and wherein theinterference cancellation module is further configured to compute aplurality of weighting factor values corresponding to the plurality ofsource-specific user signals, utilizing the plurality of interferencecancellation parameters, to provide the interference suppressed signal.8. The wireless communication device of claim 7, wherein theinterference cancellation module is further configured to compute theplurality of weighting factor values utilizing a signal power level or anoise power level of the multipath component signal, the multipathcomponent signal corresponding to a source-specific user signal fromamong the plurality of source-specific user signals.
 9. The wirelesscommunication device of claim 1, further comprising: a memory configuredto store a plurality of interference cancellation parameters, whereinthe processor is farther configured to generate the interferencecancellation parameter by selecting the interference cancellationparameter from the memory.
 10. The wireless communication device ofclaim 2, wherein the processor is further configured to compute achannel estimate value utilizing information within the plurality oflistened or non-listened BTS component signals, and wherein theinterference cancellation parameter is computed by applying a rakereceiver weighting of the plurality of listened or non-listened BTScomponent signals to the channel estimate value.
 11. A wirelesscommunication device, comprising: a rake receiver configured to providesignal source information corresponding to a plurality of multipathcomponent signals, the plurality of multipath component signalsconstituting a received signal; an interference cancellation moduleconfigured to separately process the plurality of multipath componentsignals according to the signal source information to provide aplurality of estimated interference signals; an interpolator configuredto provide a plurality of interpolated estimated interference signals;and a subtractor configured to subtract the plurality of interpolatedestimated interference signals from the received signal to provide aninterference suppressed version of the received signal.
 12. The wirelesscommunication device of claim 11, wherein the signal source informationcomprises: a rake finger channel estimate or timing; a scaling factor;or a scrambling code.
 13. The wireless communication device of claim 12,wherein the received signal comprises: a plurality of listened ornon-listened base-transceiver station (BTS) component signals, andwherein the scrambling code corresponds to a listened or a non-listenedBTS.
 14. The wireless communication device of claim 11, wherein thereceived signal comprises: a plurality of listened or non-listenedbase-transceiver station (BTS) component signals, and wherein theplurality of estimated interference signals estimate a plurality ofnon-listened BTS component signals.
 15. The wireless communicationdevice of claim 11, further comprising: a buffer configured to store thereceived signal, wherein the subtractor is further configured tosubtract the plurality of interpolated estimated interference signalsfrom the received signal stored in the buffer to provide theinterference suppressed version of the received signal.
 16. A method forsignal processing in a wireless communication device, comprising:allocating a received signal to a processing module according to asource of the received signal; weighting the received signal accordingto a received signal metric to generate an estimated component signal ofthe received signal; and subtracting the estimated component signal fromthe received signal to generate an interference suppressed version ofthe received signal.
 17. The method of claim 16, wherein the step ofallocating comprises: allocating a plurality of multipath componentsignals to separate processing modules, wherein the plurality ofmultipath component signals constitute the received signal, and whereinthe plurality of multipath component signals include a plurality oflistened or non-listened base-transceiver station (BTS) componentsignals.
 18. The method of claim 17, wherein the step of allocatingcomprises: allocating the multipath component signals to separateprocessing modules according to a pseudo-noise (PN) sequence or anorthogonal variable spreading factor (OVSF) code of the listened ornon-listened base-transceiver station (BTS) component signals.
 19. Themethod of claim 17, wherein the step of weighting comprises: weightingthe received signal according to a signal power level or a noise powerlevel of a multipath component.
 20. The method of claim 17, wherein theestimated component signal is an interference signal estimate of anon-listened BTS component signal.